This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The goal of this project is to develop and evaluate blood contacting biomaterials that incorporate the bioactive protein, CD39, an enzyme that degrades ADP and therefore may inhibit platelet activation. Candidate biomaterials are being evaluated in the baboon arteriovenous shunt model.